Results of intraoperative radiotherapy given as a boost after breast conserving-surgery

Abstract

Background: Whole breast irradiation after breast-conserving surgery (BCS) with an external beam boost of 10-16 Gy is currently the standard treatment in breast cancer. Various modalities have been used for tumor bed boost irradiation. This study aimed to evaluate the local recurrence rate, overall survival rate (OSR), toxicity and cosmetic outcome of intraoperative radiotherapy (IORT) as a boost followed by whole breast irradiation in patients who received BCS.Methods: This is a retrospective study. Between December 2009 and March 2017, 81 patients who underwent BCS with IORT as a boost were enrolled in this study. For IORT, a single dose of 20 Gy was delivered using a 30-50 kV photon beam, intraoperatively. All patients received whole breast radiation therapy (WBRT) of 42.5-50 Gy over 4-5 weeks. The primary endpoint was a 3-year local recurrence rate. Secondary endpoints included the OSR, toxicity and cosmetic outcome at 6 months after radiation treatment.Results: At a median follow-up of 43 months, ipsilateral local recurrence was observed in one of the 81 patients (1.2%) which occurred in the same quadrant of the breast index. The 3-year OSR was 89.8%.Treatment was well-tolerated with no grade 3-4 acute and late toxicity, and 87% of patients were recorded as excellent-good cosmesis.Conclusions: The use of BCS with IORT as a boost resulted in a low local recurrence rate and excellent cosmetic outcome in early breast cancer. Thus, IORT as a boost could be considered as an alternative to an external beam boost. Prospective studies are needed to confirm this data.

Long-Term Outcomes of an International Cooperative Study of Intraoperative Radiotherapy Upfront Boost with Low Energy X-Rays in Breast Cancer

“…Nonetheless, interesting hypotheses could be pondered after these findings. Other experiences published along the last decade, assessing kIORT as a boost approach, have reached similar and encouraging outcomes with follow-up times between 28 and 78 months (14,(40)(41)(42)(43). In spite of recurrence risks, classical factors, such as patient age <50, higher T and clinical stages, ET, and ypN1 outcome, were related to increased failure rates.…”

Major complications after intraoperative radiotherapy with low-energy x-rays in early breast cancer

“…Additionally, production of collagen is reduced due to restrained fibroblast proliferation and the risk of wound infections is elevated as a result of the impaired immune system [ 36 ]. However, adjuvant chemotherapy was shown to have no impact on chronic higher-grade toxicities in patients treated with IORT and WBRT [ 37 , 38 ]. Moreover, a retrospective analysis of patients who received neoadjuvant chemotherapy and subsequently underwent IORT and EBRT did not reveal any severe acute and late toxicity [ 39 ].…”

Intraoperative Radiotherapy as a Tumour-Bed Boost Combined with Whole Breast Irradiation Versus Conventional Radiotherapy in Patients with Early-Stage Breast Cancer: A Systematic Review and Meta-analysis

“…Many single-arm studies have demonstrated the efficacy and safety of IORT boost+WBI; [33][34][35][36][37][38][39][40][41][42][43] however, comparative studies on IORT boost+WBI and conventional radiotherapy are still lacking. Through a search of major databases, we screened nine comparative studies of IORT boost+WBI versus conventional radiotherapy, with varying results.…”